A while back I considered the seven wonders of the ancient world, looking for Macguffins. The Lighthouse of Alexandria, completed in 247 BC, has the legend of its reflecting mirror which could burn ships 30 miles away on the horizon.
Parabolas in civil defense were popular then, as Archimedes reportedly used one or several mirrors (and his ship-grabbing claw) across the Mediterranean to destroy Roman ships at Syracuse in 212 BC, where he died, at 75. Or maybe it was a lens. Mythbusters failed twice to replicate the experiment but some MIT students succeeded with a flat mirror array.

It wouldn't be hard to weave both mirrors into the same tale. I gave it a try here. The Macguffin seems perfect for the space race, in which a lens on a Soviet satellite in low earth orbit could adjust the focal point to just few hundred miles away on Earth. Who cares why it works while modern technology fails... that's part of the mystery!

The Macguffin seems perfect for the space race, in which a lens on a Soviet satellite in low earth orbit could adjust the focal point to just few hundred miles away on Earth. Who cares why it works while modern technology fails... that's part of the mystery!

Indiana Jones meets Die Another Day! The Icarus satellite, purportedly designed to reflect the sun's light to allow crops to be grown at any time of the year in areas facing potential famine... but capable of being focused on a particular target, creating a deadly beam of high-intensity heat. By the time this film gets made, Indy will have his own Aston Martin to outrun the beam.

This is really cool, I remembered seeing something about this on the history channel. I kinda forgot about it though, this is a nice reminder! I really like reading about things that show how advanced the ancient peoples were. It kinda feels like a mix between ancient technology and modern technology.

Archimedes may have used mirrors acting collectively as a parabolic reflector to burn ships attacking Syracuse.The 2nd century AD author Lucian wrote that during the Siege of Syracuse (c. 214–212 BC), Archimedes destroyed enemy ships with fire. Centuries later, Anthemius of Tralles mentions burning-glasses as Archimedes' weapon.[25] The device, sometimes called the "Archimedes heat ray", was used to focus sunlight onto approaching ships, causing them to catch fire.

This purported weapon has been the subject of ongoing debate about its credibility since the Renaissance. René Descartes rejected it as false, while modern researchers have attempted to recreate the effect using only the means that would have been available to Archimedes.[26] It has been suggested that a large array of highly polished bronze or copper shields acting as mirrors could have been employed to focus sunlight onto a ship. This would have used the principle of the parabolic reflector in a manner similar to a solar furnace.

A test of the Archimedes heat ray was carried out in 1973 by the Greek scientist Ioannis Sakkas. The experiment took place at the Skaramagas naval base outside Athens. On this occasion 70 mirrors were used, each with a copper coating and a size of around five by three feet (1.5 by 1 m). The mirrors were pointed at a plywood mock-up of a Roman warship at a distance of around 160 feet (50 m). When the mirrors were focused accurately, the ship burst into flames within a few seconds. The plywood ship had a coating of tar paint, which may have aided combustion.[27]

In October 2005 a group of students from the Massachusetts Institute of Technology carried out an experiment with 127 one-foot (30 cm) square mirror tiles, focused on a mock-up wooden ship at a range of around 100 feet (30 m). Flames broke out on a patch of the ship, but only after the sky had been cloudless and the ship had remained stationary for around ten minutes. It was concluded that the device was a feasible weapon under these conditions. The MIT group repeated the experiment for the television show MythBusters, using a wooden fishing boat in San Francisco as the target. Again some charring occurred, along with a small amount of flame. In order to catch fire, wood needs to reach its flash point, which is around 300 degrees Celsius (570 °F).[28]

When MythBusters broadcast the result of the San Francisco experiment in January 2006, the claim was placed in the category of "busted" (or failed) because of the length of time and the ideal weather conditions required for combustion to occur. It was also pointed out that since Syracuse faces the sea towards the east, the Roman fleet would have had to attack during the morning for optimal gathering of light by the mirrors. MythBusters also pointed out that conventional weaponry, such as flaming arrows or bolts from a catapult, would have been a far easier way of setting a ship on fire at short distances.[1]

That's how I imagine the mirror or lens, faceted and prismatic. In the novel John Carter of Mars, they explained an invisible spaceship as bending light around it by magnetizing hexagonal sand from Jupiter. It would have to be complex if the script called for a portable MacGuffin. Maybe small enough to conceal inside a jacket!

A solar glare specialist who was denied a contact by a Las Vegas hotel to help
it solve an intense sunlight issue -- now dubbed a "death ray" by employees there --
says the casino ignored his advice and went with a cheaper fix.

"It is one thing to ask experts in their relative field for advice; it is
another to ignore their advice without justification", glass film manufacturer
Nichols E. Ashton wrote the builders of the Vdara hotel back in November 2008.

I knew where you were going, and, obviously, a magnifying glass is a lens. However, a magnifying glass is not a parabolic mirror, which is what is usually associated with the Archimedes Death Ray. One could argue about "mirror lenses" and telescopes and such, but a lens and a mirror are traditionally two different things.

I was simply saying I don't think the ancients depicted would have named that little thing a Death Ray with capital letters. They would have called it something like, "Look I Can Start a Fire With A Piece of Glass."

Thanks for the image, Stoo. I couldn't make out those hand details well enough.

My guess is it's flint and steel the interdimensional being is rubbing together. Just thought I'd retcon some ancient mythology using Indy lore to craft an unreproduceable Macguffin for antagonists to pursue. Such a Macguffin's origin may be better left unexplained...

A scene from the 1961 George Pal film "Atlantis, the Lost Continent" was shown on
the NBC Today show this morning in connection with a story on a London glass building
which has been reflecting solar rays and burning up parked cars.

A scene from the 1961 George Pal film "Atlantis, the Lost Continent" was shown on
the NBC Today show this morning in connection with a story on a London glass building
which has been reflecting solar rays and burning up parked cars.

Funny, I was just coming to this thread to post about this story and you've already done so.

A few hours before you posted yesterday, I met up with fellow Ravener, Archaeos in downtown London. When our conversation turned to new architecture in the city, he told me about this very building and all the damage that it was doing. We had a good laugh and one of the first things that came to my mind was Archemides' Death Ray.

I wanted to experience the heat myself but scaffolding with a sunscreen is now in place to cover the affected area.

Saw the 1914 Italian film Cabiria. It features fiery child sacrifice that makes Temple of Doom look tame (see poster), Hannibal's elephants crossign the alps in one of several primitive split screens, and Archimedes' death ray. Here it's a huge circular array of mirrors. (The music is not original, feel free to mute it.)

U.S. Army experts revealed a Nazi plan to construct the extraordinary device. Consisting of a reflective, slightly concave disk approximately one mile in diameter, the sun gun would focus solar rays onto enemy cities -- and burn them.

Eminent German rocket scientist Hermann Oberth: "My space mirror is like the hand mirrors that schoolboys use to flash circles of sunlight on the ceiling of their classroom. A sudden beam flashed on the teacher’s face may bring unpleasant reactions."